DESCRIPTION: Falls from elevated/inclined surfaces present significant potential for debilitating accidents causing permanent disability or fatality. This three year study provides an experimental design which has the potential for investigating the interaction between age, sex and other fall risk factors such as standing surface elevation/inclination, job-task and lighting. In the proposed study, postural instability and propensity of loss of balance risk factors will be evaluated for industrial workers' performance (21 to 55 years of age) on test conditions which represent combinations of these risk factors. There are environmental (lighting), job-task (stationary versus dynamic) and personal (age) risk factors which can individually and/or collectively jeopardize one's ability to perform tasks on elevated/inclined surfaces without experiencing postural imbalance and, eventually, a fall.The intent of this application is to find answers to the following questions: (a) How do work surface inclination and elevation and distraction affect postural balance under conditions of good and poor lighting for various age ranges? and (b) What type and positioning of visual cues will be beneficial in reducing postural instability while performing simulated industrial tasks on inclined and elevated surfaces? Results obtained from the proposed study with industrial worker subjects will provide the basis for future studies using a larger sample from the worker population. For example, all test conditions (encompassing all fall risk factors) evaluated in the proposed study will be rank-ordered for propensity of loss of balance.The objective criteria used for propensity of loss of balance will be: (a) proximity of the body's sway to the subject's stability boundary as well as other loss of balance and sway parameters; and (b) number of falls experienced during the performance of simulated industrial tasks. The results from this study will: a) provide information about the types of visual needed to reduce postural instability/ propensity of loss of balance (which might put them at a risk of falling) while working on elevated or inclined surfaces; and b) help develop a statistical model showing the relationship between propensity of loss of balance and the independent variables characterizing the environmental, job-task, and personal risk factors. A determination of which of the risk factors need to be corrected to reduce the fall potential will then be possible.